Fluid pressure operated machine tool



July 16, 1935. I FOSTER 2,008,012

' FLUID IRESSURE OPERATEDMAGHINE "IROOL 7 Filed May 18. 1929 5 Sheets-Sheet l July 16, 1935.

W. H. FOSTER FLUID PRESSURE OPERATED MACHINE TOOL Filed May 18, 1929 5 Sheets-Sheet 2 l nverfiv" ZLUiZZz'amHEsier July 16, 1935.

w. H. FOSTER v FLUID PRESSURE OPERATED MACHINE TOOL Filed May 18, 1929 5 Sheets-Sheet 3 William H fisher:

July 16, 1935. w. H. FOSTER FLUID PRESSURE OPERATED MACHINE TOOL Filed May 18, 1929 5 Sheets-Sheet 4 lnveffifs ZUl ZZiam H Ester.

July 16, 1935. w. H. FOSTER 2,008,012

FLUID PRESSU E OPERATED MACHINE TOOL Filed May 18, 1929 5 Sheets-Sheet 5 Ester STA/A .I/II /flll/l ll Patented July 16, 1935 PATENT OFFICE FLUID PRESSURE OPERATED mourns William H. Foster, 1211mm, Ind.

Application May 18, 1929, Serial No. 364,110

40 Claims.

The present invention relates to fluid pressur operated machine tools.

Though the invention willbe described particularly with reference to lathes, it will appear as the description proceeds that the invention has a broader application. A description of the present invention in connection with lathes will be sufhcient, it is thought, for a complete disclosure. 7

In the operation of machine tools and other mechanisms in which a single source of fluid pressure is used for communicating movement to aplurality of movable members, difficulties have been encountered in controlling the distribution of force to said movable members, many factors, including the matter of leakage of the fluid medium, presenting serious problems. The fluid medium which is at present preferred is oil, and when the term fluid medium is used in the present specification it will be understood that oil is a preferred embodiment thereof.

An object of the present invention is to provide a machine tool or other mechanism having parts which must be positively moved in predetermined relationship with one another, which machine tool or other mechanism is provided with control means whereby the movements of said parts may be accurately predetermined.

A further object is to provide a machine tool or the like havinga plurality of relatively movable parts, together with fluid pressure -(preferably oil pressure), means for positively moving said parts, said machine tool or the like being provided with means for insuring that said relatively movable parts will move according to a predetermined relationship with one another.

- A further and more specific object is toprovide a fluid pressure operated lathe or the like having a' reciprocable platen carrying a plurality of slides which may be moved relative to said platen, together with fluid pressure responsive means for operating said platen and said slides with a predetermined relationship between said slides and said platen.

A further object is to provide a lathe or the like having a plurality of fluid pressure operated tool carrying means adapted to be operated from a common source of pressure, which lathe or the like will operate automatically according to a predetermined cycle of operation of said tool carrying members. 4

A further object is to provide an improved fluid pressure lathe having a plurality of fluid pressure operated tool carrying slides in which Referring to the drawings- 6 Figure 1 is a view in side elevation of a lathe embodying the principles of the present invenv tion;

Figure 2 is a top plan view of the structure shown in Figure 1;

Figure 3 is a view in side elevation of part of the structure shown in Figure 2, said view being taken in the direction of the'arrow 3 in Figure 2;

Figure 4 is a view in end elevation of the structure shown in the preceding figures, Figure 4 being taken as the parts are viewed looking at the tail end of the lathe; 4

Figure 5 is a sectional view taken along the planes indicated by the arrows 5-5 of Figures 1 and 2;

Figure 6 is a sectional view taken along the plane indicated by the arrows 6-6 of Figure 4;

Figure 7 is a sectional view taken along the planes indicated by the arrows 'll of Figure 6; '25 and Figure 8 is a diagrammaticview showing the layout of the fluid pressure circuitsinvolved in the structure shown in the preceding figures.

The numeral ill indicates the bed of a lathe supported by the legs l I-l l. The numeral l2 indicates a pan underlying the bed ID for receiving metal turnings and constituting a sump for cooling medium, which according to usual practice may be pumped into engagement with the cutting tool or tools of the lathe. By reference'to Figures 4 and 5 it will be noted that the bed Illincludes the ways l3|3. Said ways l3-l3 constitute supporting means for the platen M, which, as shown in Figures 4 and 5, may be held against vertical movement relative to the bed ID by means of the shouldered plates Iii-l5 secured by bolts, or otherwise, to the under side of the platen I4.

As will be described presently, said platen M has slidably mounted thereon a'plurality of tool 45 carrying slides. At the head end of the lathe and supported by the bed I0 is the headstock l6, which headstock may be of usual construction and may contain power transmitting means adapted 0 to communicate power at selectable speeds to the chuck ll. Power for communicating motion to the parts within the headstock It may be derived from the electric motor l8, which, by means of a sprocket chain I!) or other preferred driving means, may be connected up to the mechanism within said headstock IS.

The illustrated embodiment of the present invention has the advantage that the use of flexible pipes may be dispensed with. The platen |4 carries a plurality of tool supporting sliding members, together with the fluid pressure operating means for said tool supporting sliding members. Said platen also carries the pump, or other source of fluid pressure, together with the electric motor for driving said pump.

Referring particularly to Figure 3, it will be.

noted that the platen 4 is provided with the block 20 securely bolted to said platen, which block provides a support for slidably carrying the longitudinal tool slide 2|. Said longitudinal tool slide 2| is provided with the bracket 22 adapted to carry a tool holder 23 and a pilot bar 24. Said pilot bar 24 is adapted to engage within an aperture in the bracket 25 secured to the headstock l6. Said longitudinal slide 2| is also provided with the tool 24a coaxially disposed relative to the chuck IT. The longitudinal tool slide 2| is adapted to be operated by the fluid pressure responsive cylinder 26, which controls the piston rod 21, adjustably connected to the longitudinal tool slide 2|. Said operating'cylinder 26 is secured, by bolts or otherwise, to the platen l4 and therefore moves as a unit with the platen i4.

Mounted to move transversely of the lathe are 'a pair of cylinders 28 and 29, which cylinders are adapted to move relative to pistons stationarily mounted relative to the platen I4. A preferred construction of the cylinders 28 and 29 and their associated parts will be clear from an inspection of Figure 5. It will be noted that the platen I4 carries a pair of blocks 36 and 3 I, which blocks are bolted, or otherwise secured, to said platen l4. Said blocks 39 and 3| provide supports for slidably carrying the cross slides 32 and 33, respectively. Said cross slides 32 and 33 are provided with tool holders 34 and 35, respectively.

The numerals 36 and-31 indicate piston rods rigidly and adjustably secured to the blocks 39 and 3|, respectively. The means for mounting said piston rods 36 and 31 may be briefly described as follows. It will be noted that each of said piston rods is provided with a reduced extremity 33 surrounded by an externally screwthreaded bushing 39. Said bushings 39-39 are threaded into corresponding screw-threaded apertures 46-46 in said blocks 30 and 3 I. Nuts 4 4| lock said bushings firmly in position. The outer extremities of the bushings 39-39 are adapted to abut shoulders 42-42 on the piston rods 36 and 31, thereby taking the inward end thrust of said piston rods 36 and 31. The inner extremities of the reduced portions 38-38 of said piston rods 36 and 61 are threaded for the reception of nuts 43-43 and lock washers 44-44.

Each of the'piston rods 36 and 31 is provided with a piston secured thereto. The piston secured to the piston rod 36 bears the numeral 45 and the piston secured to the piston rod 31 bears the numeral 46. Said pistons 45 and 46 have relatively large portions 41 and 48, respectively, which portions have sliding fits within the cylinders 28 and 29, respectively. Said pistons 45 and 46 also have the reduced portions 49 and 50, respectively. Said reduced portions 49 and 50 have sliding fits within portions 5| and 52, respectively, of the cylinders 28 and 29. By reason of the structure referred to, annular spaces 53 and 54 are provided between the inner end walls of cylinders 28 and 29 and the enlarged portions of the pistons 45 and 46. A fluid-tight fit between the reduced portions 49 and 50 of the pistons 45 and 46 and the cooperating portions of the cylinders 28 and 29 may be insured by means of the packing glands 55 and 56. The outer ends of the cylinders 28 and 29 may be tightly closed by means of the cylinder heads 51 and 58, respectively, which cylinder heads 51 and 58 may be cored out to provide spaces 59 and 60, respectively. The piston rod 36 is provided with a longitudinal port 6| communicating with the space 59. The other extremity of said port 6| communicates with a pipe line 62, which will be referred to more in detail presently. The piston rod 31 is provided with the longitudinal port 63, one end of which port communicates with the space 60 and the other end of which communicates with the pipe line 64, which will be referred to more in detail presently. The

piston 36 is also provided with the port 65 communicating with the space 53. Said port 65 also communicates with the pipe line 66, to be referred to more in detail presently. The piston rod 31 is provided with the port 61 communicating with the space 54 and also communicating with the pipe line 68, to be referred to more in detail presently.

The cylinders 28 and 29 are shown in their innermost positions. It will be clear that when pressure is communicated through the pipe line 62 or 64, pressure will be exerted upon the cylinder heads 51 or 58, respectively, urging the corresponding cylinders outwardly. Conversely, when pressure is relieved from the pipe line 62 or 64 as the case may be and pressure is applied to the pipe lines 66 or 68, respectively, pressure will be communicated to said cylinders to move same inwardly. Said cylinders 28 and 29 are connected to the tool slides 32 and 33 by means of the brackets 69 and 16, respectively.

For a disclosure of the parts associated with thecylinder 26, which controls the longitudinal tool slide 2|, reference may be had to Figures 3 and 8. From an inspection of Figure 8 it will be noted that the cylinder 26 has one end apertured to permit the passage of the piston rod 21, leakage being minimized by means of the packing gland 12. The other end of the cylinder 26 is closed by means of the cylinder head 13. The space at the right end of cylinder 26 is indicated by the numeral 14. Adapted to slide within the cylinder 26 is the piston 15, which is adapted to be moved forwardly and rearwardly by means of fluid pressure communicated alternatively to the two sides of said piston through pipe lines which will be described presently.

The platen I4 is adapted to be operated in response to pressure within the cylinder 16, which cylinder 16 is rigid with the platen I4, being bolted or otherwise secured to said platen l4 on the under side thereof, as shown in Figure 5. By ref erence to Figure 8, the structure of the platen operating cylinder 16-and its associated parts will be clear. Slidably disposed within said cylinder 16 is the piston 11, which has connected thereto the piston rod 18. Said piston rod 18 has its outer extremity screw-threaded, as indicated by the numeral 19. Said screw-threaded portion 19 is adapted, through the medium of the adjusting nuts 80-80, to be adjustably secured to the bracket 6|, bolted or otherwise secured to the bed H) of the lathe. Pressure may m communicated alternatively to the two ends of the cylinder 16, which pressure, coacting with the piston 11, will move the cylinder, and with it the platen i 4, forwardly or rearwardly, depending upon the disposition of said pressure on one or the other side of the piston ll.

The numeral 82 indicates a fluid pressure pump (Figs. 2, 3, 4 and 8). Said pump is carried by the platen I4 and is adapted to be driven by the electric motor 83 also carried by the platen M. A sprocket chain 84 communicates driving power from the motor 83 to the pump 82. Said pump 82 is provided with the control valve 85 having a plunger 86 (Figs. 4 and 8). The position of said plunger 86 controls the direction of flow of the fluid pumped by said pump 82 and also controls the rate of flow per unit of time. Aswill be described presently, the plunger 86 of valve 85 may be positioned selectably to cause the pump 82 to pump fluid at a relatively high rate per unit of time to cause rapid traverse movement of the platen I4, or the tool carrying slides H, 32 or 33. Said plunger 86 of the valve 85 may also be selectably positioned to deliver fluid in an amount per unit of time requisite for the feeding or cutting actions of the tools carried by the tool carrying slides H, 32 or 33. Said positions (indicated in Figs. 4 and 8) are as follows:

a-position for rapid traverse forward movement of the platen I l or slides EI, 32 and 33;

bposition for feeding or cutting movement of platen I4 or slides 2I, 32 and 33;

c-neutra1 position for zero movement of the platen I4 or slides 2I, 32 and 33;

d--position for feeding or cutting retreating movement of platen I I or slides 2|, 32 and 33, which position is not utilized in the illustrated embodiment of the present invention; and

e--position for rapid traverse retreating movement of the platen I4 or slides 2i, 32 and 33.

The particular pump chosen for illustration includes a control lever 81 for modifying the rate of flow of fluid from the pump 82 to vary the feeding speeds of the tools carried by slides 2I, 32 and 33. A locking lever 88 is provided for locking the control lever 81 in any preferred position. The numeral 89 indicates a governing cylinder having a piston 90 therein (Fig. 8). Pipe lines communicate with said cylinder 89 on the two sides of the piston 90, whereby said piston may be moved by means of fluid pressure delivered by the pump 82. Said piston 90 is secured to an extremity of the plunger 86. Pressureis applied to the piston 90 in the governing cylinder 89 only momentarily, and at other times said plunger 86 may be manually operated. Moreover, said plunger 86 may be operated by certain cams, to be referred to presently, operative in response to movement of the platen I6. For manually operating the plunger 86 of the control valve 35, the handle 9| is provided (Figs. 2 and 4) As will be seen from Figure 4, said handle BI is pivotally connected to the plunger 86. The pivotal connection between the handle 9I and the plunger 86 should be a loose one, whereby to avoid binding. For the purpose of providing the loose connection referred to, the handle 9I is provided with transversely extending studs 9Ia adapted to ride in elongated slots 92a in the bifurcated end portion of the plunger 86. Said handle BI is pivoted intermediate of its length to a bracket 02 bolted or otherwise secured to the platen It. The lower extremity of the handle EII is pivotally connected to one end of the extensible strut 93, the other end of which is pivotally connected to the roller holding member or slide 94. Said roller holding member or slide 94, as shown in Figures 4, 6 and 7, is slidably mounted in a bracket bolted or otherwise secured to the under side of the platen M. Said bracket 93 guides the roller holding member or slide 93 in a right line movement transversely of the lathe; The inner extremity of the member 94 isprovided with the roller 96 adapted to be engaged selectably by the cam 91 or the cam 36. Said cams Q'i'and 98 are adjustably carried by the angle member 99 (Figs. 4, 6 and 7), which angle member is boltedor otherwise secured to the bed I0 of the lathe. One leg of said angle member 99 is horizontally disposed and is provided with elongated slots I00--I00, whereby the cams 9i and 98 may be adjusted longitudinally relative to said angle member 99.

The pipe lines, valves and other members for controlling the flow of fluid from the pump 82 to the instrumentalities above mentioned will now be described.

Referring to Figure 8, the numeral IOI indi cates a pilot valve comprising the cylinder wall I02 and the two cylinder heads I03 and I04. Said cylinder heads in themselves comprise cylinders for receiving the two extremities of the plunger I05 of said pilot valve IOI. Said plunger I05 includes the two relatively large annular portions -I06I06 providing between them the annular space I07. Said portions I06 also provide the spaces I08-I08 at the two extremities of the cylinder wall I02. Communication is had between the two spaces I08--I08 at the two ex-- tremities of the cylinder wall I02 through the aperture I09. Communicating with'the cylinder head I03 is the pipe line IIO, and communicating with the cylinder head I03 is the pipe line I I I. As will be explained presently, pressure will be applied selectably through pipe connections H0 and I I I to move the plunger I05 to one extreme or the other of its travel. Communicating with the annular space I01! is the pipe line I I2, which pipe line H2 leads from the pump 82 'and always has a pressure therein so long as the pump 02 is being operated. It may be stated at this point that the pressure delivered through pipe line H2 may be relatively low. The space I08 adjacent tothe cylinder head I03 is adapted to communicate with the pipe line II3 when the plunger "I05 is at the right-hand part of its travel as the parts are viewed in Figure 8. When said plunger I05 is in the lefthand part of its travel, communication between the space I68 adjacent to the cylinder head I03 and pipe line II3 will be interrupted by the left hand relatively large annular portion I06 of said plunger I05. Said pipe line II3 leads to the space to the left of the piston 90 in the'governing cylinder 89.

The numerals II i, II5, H6, H1, H8, IIS, I20 and HI indicate resistance valves. Of said valves, those bearing the numerals II 4 and II 6 are shown as similar in structure, though they may differ in calibration. Valves H5, H1, H0, H9, I 20 and I2I may be similar in construction to valves H41 and II 6 (though differing in calibration therefrom) but have been illustrated as of slightly different form merely for the reason that in an actual embodiment of the present invention the corresponding valves were different from the valves corresponding to valves II4 and II8 herein. The difierences noted were provided in the actual embodiment mentioned for the reason that due to their position on the lathe, it was convenient in some instances to have the adjusting screws thereof at the tops of said valves and in other instances it was convenient to have said adjusting screws at the bottoms of said valves. A description of resistance valve H4 will suffice for a description of resistance valve H6 as well.

on the periphery of said plunger.

Each of said resistance valves I I4 and H6 includes a cylinder I22 having a plunger I23 therein spring-pressed upwardly by means of the spring I24, the tension of which spring may be adjusted by means of the screw I25. Said screw I25 may be locked in adjusted position by means of the lock nut I26. The plunger-I23 is provided with the longitudinally extending aperture I21 providing the valve seat I28, which valve seat I28 carries the valve member I29. The plunger I23 has a bearing surface I30, preferably conical in contour, bearing against the upper head of the cylinder I22. The spring I24 normally holds the plunger I 23 in liquidtight engagement with the upper head of the cylinder I22, but when sufficient pressure is exerted upon the upper side of the plunger I23, said plunger I 23 will be forced downwardly. The plunger I23 is provided with the longitudinally extending groove I3I on its periphery, which provides communication from the bottom side of the plunger I23 to the top side thereof independently of the longitudinal aperture I21. It will be clear that the fluid directed under pressure into the space below the plunger I23 will flow past the valve I29 without interference. When the direction of fluid pressure is reversed however, and said pressure is applied to the topside of the plunger I23, the passage of fluid through the aperture I21 will be prevented by the valve member I29. No fluid will pass until suiiicient pressure has been applied to the top side of the plunger I23 to move said plunger from its seat against the action of the spring I24. When sufiicient pressure is applied to move said plunger I23 from its seat, fluid may flow past the surface I30 of said plunger I23 through the groove I3I to the space below the plunger I23.

Resistance valves H5, H1, H8, 9,. I20 and I2I are similar to one another in structure, but may be differently calibrated. A description of one of said valves will suffice for all. Each of said valves comprises a cylinder I32 having slidably disposed therein a plunger I33, which plunger is urged to one extremity of the cylinder I32 by the spring I34. The tension of saidspring I34 may be adjusted by means of the screw I35, which may be locked in adjusted position by means of the lock nut I36. The plunger I33 in the illustrated embodiment of the present invention is urged downwardly by the spring I34 and is provided with a conical bearing surface I31 adapted to engage a similar surface in the head of cylinder I 32. Disposed longitudinally of the plunger I33 is the aperture I38, which provides a seat I39 for a valve member I40. Said valve member I40 is held upwardly against said seat I39 by means of the spring I4 I. The plunger I33 is provided with a longitudinal groove I42 Said groove I42 extends from one side of the plunger I33 to the other side thereof. It will be clear that if fluid is delivered to the space above the plunger I33 under sufiicient pressure to move the valve member I40 from its seat, said fluid may pass through the aperture I38. On the other hand, when fluid under pressure is communicated to the lower side of the plunger I 33, said valve I40 will prevent the passage of said fluid through the aperture I36. When pressure within said fluid applied to the lower side of the plunger I33 is at or above a predetermined value, the plunger I33 will be moved upwardly against the tension of the spring I34, moving the surface I31 out oi. engaging relationship with the lower head of the cylinder I33, permitting the flow of fluid said surface I31 through the groove I42 to the space on the upper side of the plunger I33.

It will be noted that in the valves H4 and I I6 gravity holds them valve member I 28 upon its seat, and in the valves H5, H1, H8, II9, I20 and I 2| the spring I4I holds the valve member I40 upon its seat. Said spring I4I should be a relatively weak spring offering no substantial resistance to the flow of fluid downwardly through the aperture I38.

The control valve 85 is provided with three pipe lines I43, I44 and I45. Pipe line I43 leads to the coupling I46, from which the pipe line I41 leads to the resistance valve I I having communication to the space below the plunger I33 thereof. Also leading from the coupling I46 is the pipe line I48, which leads to the coupling I49. Leading from the coupling I49 is the pipe line I50, which communicates with the space below the plunger I23 of the resistance valve II 4. Also leading fro-m the coupling I49 is the pipe line I5I, which leads to the space on the upper side of the plunger I 23 of the resistance valve H6. The space below the plunger I23 of resistance valve IIG connects with pipe line 62. The space above the plunger I23 of resistance valve II 4 leads through the pipe lin I52 to the space at the left side of the piston 11 in the platen operating cylinder 16. The space at the right side of said piston 11 communicates through the pipe line I53 to the coupling I54. Leading from said coupling I54 are the pipe lines I55, I56 and I51.

Pipe line I56 leads to the coupling I58, from which pipe line I59 leads to the coupling I60. From the coupling I60, pipe line I44 leads back to the control cylinder 85.

Pipe line I51 connects the coupling I54 with the space on the under side of the plunger I 33 of the resistance valve I I9. The space above said plunger I33 of resistance valve I I9 communicates with the pipe line I6I, which pipe line leads to the coupling I62. Said coupling I62 is connected, through pipe line IIO, with the cylinder head I03 of the pilot valve IOI. This connection provides communication with the plunger I05 01 said pilot valve IOI. From the coupling I62 leads the pipe line I64, which pipe line includes the restricted orifice member I65. Said pipe line I64 is connected to the coupling I65a. Said coupling I65a has connected thereto the pipe line I66 and the pipe line I61. Pipe line I61 leads to the coupling I68. To coupling I68 are connected the pipe lines I69 and I 10. Pipe line I leads to the coupling I1I. Coupling IN is connected to the pipe line I45 leading to the control cylinder 85. Said coupling IN is also connected, through the pipe line I12, to the space at the right of the piston 90 within the governing cylinder 69.

Pipe line I66 is connected to the coupling I13, to which are connected the pipe line I14 and the pipe line I 15. Said pipe line I14 is connected to the longitudinal aperture I09 of the pilot valve i0i. It will be noted that with the parts as indicated in Figure 8, pipe line I14 has access through the space I06 adjacent to the cylinder head I 03 of pilot valve IOI to the pipe line II3 leading to the space at the left of the piston 90 of the governing cylinder 89.

The pipeline I is provided with the restricted orifice member I16. Said pipe line I15 connects with the coupling I11, from which lead the pipe line I13 andpipe line I19. Said pipe line I18 leads to the cylinder head I04 of the pilot valve pressure will be delivered through pipe lines M3,

MI, and provides communication to the righthand extremity of the plungeriil5. Pipe line H9 leads to the space above the plunger I33 of the resistance valve H5. As noted above, the space below said plunger I33 'of valve- H5 communicates through pipe line MT! and coupling iii to the pipe line M3.

The coupling I58, which connects pipe line M6 to pipe line H59 also connects with the pipe line I80, which leads to the space below the plunger in the resistance valve Iii. The space above the plunger in said resistance valve ii! is connected through the check valve IBI to the coupling I82. Said check valve iBi, it will be noted, will permit flow of fluid from the resistance valve III'I through said check valve, but will stop the flow of fluid in the opposite direction. Said coupling it? has connected thereto the pipe line .ifiii leading to the space-at the right of the piston I5 in the longitudinal slide operating cylinder 26. Said coupling I82 also has connected thereto the pipe line I84, which leads to the coupling i85. Said coupling I85 is connected, through the pipe connection H86, to

'- the space below the plunger of the resistance valve H8. The space above the plunger in re- I sistance valve I I8 is connected, through the pipe line IIBT, to the coupling I88. Said coupling ltd has connected thereto the pipe line Hi9, above referred to,- and the pipe line i853. Said coupling ltd connects with the pipe line 68.

The coupling itii is connected, through the pipe line tilt, to the space below the plunger of the resistance valve I20. The space above said plunger in said resistance valve i2ll connects with the pipe line IN, which pipe line includes the check valve I92. Said check valve II 92 is so designed that it will permit flow of fluid from said valve till, but will stop flow of fluid in the opposite direction. Said pipe line it! is connected to the coupling I92o. Said coupling M20 is connected to the pipe line t6 above mentioned, and is also connected to the pipe line W3. Said pipe line M3 is connected to the coupling 9%. Said coupling IN has connected thereto the pipe line MI abovernentioned and the pipe line W5. Said pipe line it leads to the space below the plunger in the resistance valve I2I. The space above said plunger in said resistance valve H26 isconnected to'the pipe line I89 above mentioned.

. A mode of operation of the present invention means of the handle ill the oil or other fluid under pressure being traced as briefly as possible. The source of fluid pressure is the pump 82, which has. cooperatively associated therewith the control valve 85 and the four pipe lines H2, I43. I44 and M5. Assuming that the platen it, the longitudinal slide M and the cross slides 32 and 33 are all in retracted positions, and assuming that the operative desires to start a cycle, he will, by (Fig. 4), move the plunger of the control valve 85 to position a (Figs. 4 and 8), which is the rapid traverse forward position. In using the term retracted position with reference to the platen it and the longitudinal slide 2I, it is meant that said members are at-the right-hand extremities of their 5 ranges of movement, as the parts are viewed in Figures 1, 2 and 8. With reference to the cross slides 32 and 33, it is meant that said cross slides are at the limits of their move- ,ment towardthe longitudinal center line of the lathe. Under these conditions, fluid under I48 and I50 through resistance valve IM (flow of fluid in this direction being without resistance) through pipe line I52 into the space to the left of the piston 'I 'I within the platen operating cylinder 16.- As' has been noted hereinbefore, said cylinder is rigidly secured to the platen i4, and the piston llthereof is rigidly though adjustably secured to the bed ID of the lathe.

Fluid is prevented from passing through pipe lines Ml and IM at this time by the resistance valves M5 and H6, respectively, until the cylinder I6 has reached its limitof travel in a left- I hand or forward direction as the parts are viewed in Figures 1, 2 and 8. Usually this limit of travel' will be determined by adjustment of the nuts 80-80 on the threaded extremity of the piston It is within the scope of the present invention to provide mechanism whereby the lathe may be controlled so that the platen M may move not only with a rapid traverse movement for carrying the tool carrying slides 2i, 3'2 and 33 forwardly to operative positions, but, if desired, the platen may be moved ata feeding speed during the-finishing operation of its forward movement. The choice of whether or not the platen I4 will be slowed down to a feeding speed during the finishing part of its'movement may be made by adjusting the cam 91 (Figs. 6 and 7). Said cam Elli may be so positioned that before the platen it reaches the end of its stroke in a forward direction, said cam Bl will engage the roller 96, resulting in the movement of the slide it and handle 90 to position b (Figs. 4 and 8), which is the position for forward feeding movement. That is to say, position b is the position wherein the valve 85 will control the output of the pump 82 to cause the delivery of a restricted quantity of fluid per unit of time. The roller 96 will continue along the high part of the cam 91 travel. If no feeding speed is desired in the movement of the platen it, said cam 91 will. be so positioned that it will operate the roller 96 to move the plunger 88 to position I), just as the end of the stroke of the cylinder 16 is reached. During the forward movement of the platen immediately above described, fluid will be returned from the right-hand end of cylinder FIG through the pipe lines 653, E56, I59 and IM to the pump 32. v

Pressure will new build up in pipe lines M3, I 48 and ibl. The resistance of resistance valve H6 will be chosen of a lower value than the resistance of the resistance valve H5. Fluid will therefore pass through resistance valve Mt, pipe line 62 and pawageway ti to the space 59 at the end of the cross slide operating cylinder 28, causing said cylinder to move outwardly, carrying with it its corresponding tool slide 32.

While said cylinder 2% is moving outwardly carrying with it its corresponding tool slide 32,

fluid will be forced out of the space 53 in the cylinder 26, through the port '65, pipe lines 66,

I93 and M, to the port 53 within the piston of 61 and pipe lines 68, I84 and I-83 into the space 14 at the right-hand end of the longitudinal slide operating cylinder 26, causing forward movement of the longitudinal slide 2 I. At this time fluid on the left-hand side of the piston 15 within the cylinder 26 is returned through pipe lines I 55, I56, I59 and I44 to the pump 82.

After the cylinders 28 and 29 and. the piston 15 have completed their strokes, pressure will build up sufliciently in pipe line I43 to pass fluid through the resistance valve II 5, whence fluid will pass through pipe lines I19 and I18, and will shift the plunger I05 within the pilot valve IOI toward the left as the parts are viewed in Figure 8, causing communication from pipe line II2 through pipe line II3 to the left end of the governing cylinder 89, causing the plunger within the control valve 85 to move to the right as the parts are viewed in Figure 8, moving said plunger to position e, which is the position for controlling the pump 82 to cause rapid traverse retreating movement of the platen I 4- and slides 2|, 32 and 33 to starting position.

At this point the relative volumes of the cylinders above mentioned may be discussed.

As noted above, after the platen I4 has completed its stroke in a forward direction through the operation of the cylinder 16, pressure builds up sufficiently within the pipe line I5I to force fluid through the resistance valve I I6 to the space 59 within the cylinder 28. The maximum volume or capacity of the space 53 within the cylinder 28 will be chosen slightly greater than the volume of the space 60 within the cylinder 29. Moreover, the volume of said space 54 will be chosen slightly greater than the volume of the space 14 within the cylinder 26. Thus it will be seen that if no leakage occurs past the pistons within the three cylinders last mentioned, the piston within cylinder 26 will reach the end of its stroke first. When said piston 15 has reached the end of its stroke, the cylinder 29 will not have reached quite the end of its stroke. Therefore, a. small quantity of fluid will be forced through port 61, pipe line 68, pipe line I86, resistance valve H8 and pipe lines I81, I69, I10 and I45 to the pump 82. In like manner, when the cylinder has reached the end of its stroke, cylinder 28 will not have reached the end of its stroke, and a small quantity of fluid remaining in the space 53 of cylinder 29 will be forced out through the port 65, pipe lines 66, I93 and I95, resistance valve I2I, pipe lines I89, I69, I10 and I45 back to the pump 82. When the cylinder 28 has reached the end of its stroke, pressure will build up in pipe lines-I43 and I41, opening resistance valve II 5, shifting the plunger I05 of the pilot valve IM to the left as the parts are viewed in Figure 8. Fluid pressure within the pipe line II2 now communicates through the annular space I 01 Within the pilot valve I8I through the pipe line II3 to the space at the left of the piston within the governing cylinder 89, resulting in the movement of the plunger 86 of control valve 85 to position e, which is the position for rapid traverse retreating movement.

With the plunger of the valve in position e, fluid will now be delivered through the pipe line I44, pipe lines I59, I56 and I55 to the space at the left of the piston 15 within the longitudinal slide operating cylinder 26, causing the retreating movement of said piston 15 and its corresponding longitudinal tool slide 2 I. Fluid will be forced out of the space 14 at the right-hand end of the cylinder 26 to pipe lines I83, I84 and 68, port 61 of cylinder 29 to the space 54 within said mature shifting of the pilot valve I01.

cylinder 29, resulting in the retreating movement or inward movement of said cylinder 29 and its corresponding cross slide 33. 'Fluid will be forced out of the space 60 through the port 63 to pipe lines 64, I93 and 66 and port 65 to the space 53 within the cylinder 28, resulting in the retreating or inward movement of said cylinder 28, which cylinder moves the corresponding cross slide 32 in its retreating movement toward the longitudinal center line of the lathe.

The fluid in the space 59 of the cylinder 28 passes through port 6I to pipe line 62. through the resistance valve I I 6, which presents no resistance to flow in this direction, through pipe lines I5I, I48 and I43 to the pump 82. As indicated above, the maximum volume of the space 14 within the longitudinal slide operating cylinder 26 is somewhat less than the maximum volume of the space 54 Within the cross slide operating cylinder 29. Consequently, the fluid from the space 14 cannot completely accomplish a retreating stroke of the cylinder 29. Therefore, an auxiliary fluid supply is provided for completing the retreating movement of said cylinder 29. Such auxiliary supply is provided through the pipe line I80, resistance valve II1, check valve I8I, pipe lines I84 and 68. Likewise, inasmuch as the volume of the space 68 within the cylinder 29 is less than the max1 mum volume of the space 53, the fluid from the space 60 cannot cause the complete retreating movement of the cylinder 28. An auxiliary fluid supply to complete the retreating movement of the cylinder 28 is provided through the pipe line I90, resistance valve I20, check valve I92, pipe lines I9I and 66 to the port 65. During the retreating movements of cylinders 28 and 29 and the piston 15, fluid was prevented from passing through pipe line I53 to the platen operating cylinder 16 by the resistance valve I I4. It will be noted that the fluid in the left end of the cylinder 16 must be returned through pipe line I52 and resistance valve II4, the resistance of valve I I4 being sufficient to prevent movement of the cylinder 16 until the cylinders 28 and 29 and the piston 15 within the cylinder 26 are fully retreated.

After said cylinders 28 and 29 and said piston 15 are fully retreated, the pressure will build up in pipe line I53, causing movement of the cylinder 16 in a retreating direction, carrying with it the platen I4. At a predetermined position, the cam 98 (see Figs. 4, 6 and 7) will engage the roller 96 disposed in cooperative relationship with the slide 94, strut 96, handle 9I and plunger 86. The cam 98 will produce the gradual shifting of the plunger 86 until position 0 is reached, which terminates the cycle of operation. During the retreating movement above described, there is pressure in the pipe line- I56 sufficient to force fluid past the resistance valve II9 through pipe lines IISI and H0. Thus fluid under pressure will be applied to the left-hand end of the plunger I05 of the pilot valve I 0|, shifting said plunger 05 to the right, cutting off communication from pipe line II 2 through pipe line II3 to the control cylinder 89. As noted above, the pressure within pipe line II2 is always in the same direction and is always existent while the electric motor 83 is driving the pump 82.

The restricted orifice members I16 and I65 are provided to permit any slight leakage which might occur through resistance valves II 5 and H9 to enter the drain line It? through pipe lines I10 and I45 back to the pump 82, thereby avoiding a pre- However,

the openings through said restricted orifice members are sufficiently small so that when resistance valves H5 and H9, respectively, are forced open and fluid flows through said valves, the volume of loss through said restricted orifice members I18 and I65 is not sufficiently great to interfere with the shifting of the plunger I05 of the pilot valve I M.

lit will be understood, of course, that in setting up the lathe for operation, the resistance valves will all be adjusted whereby said resistance valves will open in the preferred sequence. It will also 'be understood that if it should be preferred to move the cross slides 32 and 33 inwardly during the cutting stroke, the structure may be readily altered to anchor the cylinders to the bases and to connect the pistons to said cross slides.

With particular reference to the resistance functions of .the resistance valves III and I20, it may be stated that resistance valve I II will be so calibrated that its resistance is somewhat greater than the pressure required in pipe lines I56 'and I55 to return the piston I5 in the longitudinal slide operating cylinder 26 to its retreated position. After said piston 15 has reached the limit of its retreating movement, that is-in its extreme right-hand position as the parts are viewed in Figure 8, pressure will build up in pipe line I44 suflicient to pass fluid through the pipe lines I59 and I80, resistance valve III and check valve I8I. Communication is now had through pipe line I83 to the space I4 at the right of the piston 15 and also to the pipe line I84. The pressure building up in pipe line I44 also communicates through pipe lines I56 and I55 to the space at the left of the piston I5. Inasmuch as the pressure applied through pipe line I80, resistance valve II! and check valve I8I will be reduced by the action of the resistance valve III, it will be clear that the pressure on the left-hand side of the piston I5 is considerably'greater than that communicated to the right-hand side of said piston through the pipe line I83. Therefore, said piston I5 will remain in retreated position.

Moreover, the resistance of the valve I20 is somewhat greater than the pressure required to open the resistance valve III. After the fluid has passed valve III and check valve I8I, it will, by way of pipe lines I84 and 58, flll the space 54 Within the cylinder 29. Pressure in pipe line I44 will build up higher, forcing fluid through valve I20, check valve I92, pipeline I9I and pipe line 66 into the space 58 within the cylinder 28. In the meantimey'resistancevalve II4 has offered sufficient resistance tothe passage of fluid to cause back pressure in the left-hand end of cylinder I6 so that after fluid has passed valve I20 and filled the space 53 within the cylinder 28, pressure will again rise to sufficient value inpipe lines I44, I59, I58 and I53-and piston I1 and pipe line I52 to overcome the back pressure of the'resistance'valve H4. It is understood, of course, that during the retreating movement of the tool slide cylinders 28 and 29 and the piston I5, the fluid in the space 59 of cylinder 28 will return through port GI, pipe line 82, resistance valve IIG (the flow being free in this direction), through pipe lines I5I, I48 and I43 to the pump 82.

' After the tool slide cylinders 28 and 29 and the piston I5 have been returned to their extreme retreated positions and the cylinder I6 moves in a retreating direction, the fluid on the left side of the piston 11 within said cylinder It will be returned through the pipe line I52,

resistance valve 4 (valve II4 offering resistance in this direction), thereby delaying the retreating operation of cylinder I6 until after the cross slides 32 and 33 and the longitudinal slide 2I are fully retreated. From the resistance valve II4, fluid passes through the pipe lines I50, I48 and I43 to the pump 82. i

It will be noted that the power required to operate the cylinders 28 and 29'and the piston I5 is supplied by the pressure delivered to the space 59 within the cylinder 28. Part of this power is used up in operating the cylinder 28. In moving outwardly, the cylinder 28 expels fluid from the space 53 through the port 85, pipe line 86, pipe line I94 and port 53 to the space within the other cross slide operating cylinder 29. Power is consumed in operating said cylinder 29, but operation of said cylinder 29 in an outward direction results in the expulsion of fluid from the space 54 within said cylinder 29 through pipe lines 88, I84 and I83 to operate the piston I5 within the longitudinal slide cylinder 28. Accordingly, the pressure in pipe line I84 is less than in pipe line 88, and the pressure in pipe line 66 is less than in pipe line 62. Therefore, the resistance valve II8, being calibrated to discharge the excess fluid from the space 54 within cylinder 29 after the space I4 within the cylinder 28 has been filled, need be set only to a resistance somewhat greater than is required to operate the piston I5 within the cylinder 28.

However, the resistance valve I2I should be calibrated to a value to respond to a pressure somewhat greater than the pressure required in pipe line 68 to operate the cylinder 29 and piston I5. It will be noted that during the retreating movements of the cylinder 29 and the piston 15, fluid is prevented, by the check valve I92, from passing out through the valve I20. At the same time fluid is prevented by the check valve I8I from passing out through the resistance valve III. Said fluid is therefore operative to move said cylinder 29 and said piston I5.

Recapitulating certain salient features of the mode of operation of the described embodiment of the present invention, let it be assumed that the parts are all in their retreated positions.

Under these conditions, the platen operating cylinder I6 may be in the position shown in Figure 8, wherein said cylinder I6 is only midway of its possible range of movement. The longitudinal slide operating piston I5 is at the righthand end of its'corresponding cylinder 26, and the cross slide operating cylinders 28 and 29 are at the innermost limits of their ranges of travel. If the operative desires to start operations, he will move the plunger 86 to position a, which,

as explained above, will cause the delivery of fluid under pressure from the pump 82 through the pipe line I43, through the resistance valve II 4, to the left end of the cylinder I6. At this time fluid from theright end of cylinder I6 may discharge through the pipe line I53 back to the pump 82. Under these conditions the cylinder 18 will move to the left. As explained above, position a of the plunger 88 is the position which causes the pump 82 to deliver a relatively large quantity of fluid per unit of time, whereby a rapid traverse movement is communicated to the cylinder I6, resulting in the rapid traverseforward movement of the platen I4. When said platen I4 has moved to a predetermined position, roller 99 (Figs. 4, 6 and 7), being carried forward with said platen' I4, will be engaged by the cam 91 (Figs. 4, 6 and 7), moving said roller and its slide 94 outwardly, resulting in the moving of the handle 9| and the plunger 86 to position b (Figs. 4 and 8). Position b corresponds to a forward feeding movement, which means that the pump 82 is so controlled by the control valve 85 that a relatively small quantity of fluid per unit of time is delivered by said pump 82. Said cam 91, being adjustable, may be so set that the plunger 86 is moved to position b before the platen operating cylinder I6 has quite reached the end of its stroke; or, if preferred, said cam 91 may be so set that the plunger 86 is moved to position b at substantially the instant that the cylinder I6 reaches the end of its movement in a forward direction.

After the cylinder 16 has moved to the left as the parts are viewed in Figure 8, to the limit of its movement, fluid pressure delivered by the pump through the pipe line I43 will build up to a sufficient value to force open the resistance valve I I6, resulting in the delivery of fluid to the space 59 within the operating cylinder 28. Said cylinder 28 and cross slide 32 will therefore move outwardly from the center line of the lathe in a feeding or cutting movement. While said cylinder 28 is moving outwardly, fluid is discharged from the space 53 within said cylinder 28 through the pipe line 66 to the space 60 within the operating cylinder 29. which operates the cross slide 33. Therefore, outward or cutting movement of the cross slide 32 will be accompanied by outward or cutting movement of the cross slide 33. As the operating cylinder 29 moves outwardly, fluid will be discharged from the space 54 within said operating cylinder 29 through the pipe line 68 to the space "I4 at the right of the piston I5 within the longitudinal slide operating cylinder 26. This action will result in the movement of the piston in a forward or feeding movement, causing a like movement in the longitudinal slide 2|. Therefore, simultaneous feeding movements will be had in the two cross slides 32 and 33 and the longitudinal slide 2|.

As indicated above, in order to compensate for leakage, it is necessary to provide a larger storage capacity in the space 53 than in the space 60. Likewise, it is necessary that the maximum capacity of space 54 be greater than the maximum capacity of the space I4. By reason of these relative proportions of the capacities of the spaces referred to, it is insured that said cylinders 28 and 29 and said piston I5 will move to their full limits of travel in their cutting or feeding movements. In practice it will be preferred to overcompensate rather than undercompensate for the leakage of fluid referred to, and therefore the longitudinal slide will reach its limit of movement first, ,after which the cross slide 33 will reach its limit of movement, after which the cross slide 32 will reach its limit of movement.

After the cross slide 32 has reachedits limit of movement, which means that the cylinder 28 has reached its limit of movement, the pump can no longer deliver fluid through pipelines I48, I5I and 62, and pressure in pipeline I43 will build up to a sufficient value to force open the resistance valve II5, passing fluid' to the right-- hand end of the pilot valve I0 I, moving the plunger I85 of said pilot valve toward the left as the parts are viewed in Figure 8. With the plunger I05 in its left-hand position, communication is had through the pipe line II2, which is always under relatively low pressure, to the pipe line I I3. Fluid entering the pipe line I I3 will be applied to the left-hand side of the piston 99 in the control cylinder 89, moving said piston and the plunger 86 to the right, that is-to position -e, which is the rapid traverse retreating position of said plunger 83. Fluid leaking past the piston 90 will drain back through connections I12 and I45 to the sump. Expressed in other language, under these conditions the pump 82 will deliver a relatively large quantity of fluid per unit of time.

Under these conditions fluid will be delivered through the pipe line I44, through pipe line I55, to the left-hand end of the longitudinal slide operating cylinder 26, resulting in the movement of the piston I5 in a retreating movement at a rapid traverse rate, which is to say that the longitudinal cylinder to move toward the longitudinal center line of the lathe, which is to say that the cross slide 33 is moved toward the longitudinal center line of the lathe. This movement will be at a rapid traverse rate. Movement of the cylinder 29, toward the center line of the lathe will be accompanied by the discharge of fluid from the space 68 within said cylinder 29 through pipe line 66 to the space 53 within the cross slide operating cylinder 28. This will cause a movement of the cylinder 28 and corresponding movement of the cross slide 32 to the longitudinal center line of the lathe with a rapid traverse movement. This movement will be accompanied by the discharge of fluid from the space 59 through pipe line 52, through resistance valve II6 (which offers no resistance to flow in this direction), pipe lines I5I, I48 and I43 back to the pump 82. It will be remembered that the capacity of the space I4 at the right of the piston 15 is less than the capacity of the space 54 within the operating cylinder 29; also that the space 69 is of less capacity than the space 53 within the operating cylinder 28. Means are provided for making up the deficit in the amount of fluid pumped to operating cylinder 29 and to operating cylinder 28. When the piston 15 has reached the end of its stroke in a right-hand direction as the parts are viewed in Figure 8, fluid within pipe lines I44, I59 and I80 will build up to a sufiicient value to open resistance valve II'I, delivering fluid through check valve |8I and pipe lines I84 and 68 to fill the space 54 to capacity.

Likewise, when the cylinder 29 has reached the limit of its travel in aninward or retreating direction, pressure will be built up within the pipe lines I44 and I90 to a sufiicient extent to open the resistance valve I20, causing the flow of fluid through the check valve I92 and pipe line to fill the space 53 of cylinder 28 to capacity, resulting in the full inward movement of the cross slide 32. After the slides 2|, 32 and 33 are all at the limits of their movements in retreating directions, pressure will buildup sufficiently in pipe lines I44, I59, I55 and I53 to deliver fluid to the right-hand end of platen operating cylinder 16, overcoming the resistance of the resistancevalve H4. Fluid will therefore be discharged from the left-hand end of cylinder I6 through said resistance valve I I4 back through pipe lines I48 and 43 to the pump 82. The fluid under relatively high pressure within pipe lines I44, I59 and I56 as above mentioned will also result in the opening of the resistance valve II8, applying fluid to the left-hand end of the plunger I05 and. the pilot valve IOI, moving said plunger back to its righthand position as shown in Figure 8, cutting off communication between the pipe line I I2 and the control cylinder 89.

According to the layout illustrated in the drawings, the 01 position of the plunger 86 is not utilized. Said (1 position, as noted above, is the position for feeding movement in a retreating direction; or, expressed in other language, is the position for controlling the pump 82 to deliver a reduced quantity of fluid per unit of time to cause retreating movements of the slides 2|, 32 and 33 and the platen I4. It will be understood without explanation that if it should be desired to utilize the position d, or if any change in the movements above specifically referred to should be desired, said changes may be accomplished by modifying the design of the cams carried by the angle member 99.

With the construction illustrated, the platen I4 will be moved in consequence of movement of the cylinder 16, until the cam 98 engages the roller 96 to move the slide 94, handle 9! and plunger 86 to position 0, which is the neutral position of said plunger 86. When plunger 86 reaches position 0, the pump 82 will be inoperative to deliver fluid through either the pipe lines I43 or I44. The parts will accordingly come to rest at a position corresponding to the setting of said cam 98, which, asindicated above,may correspond to a mid position of the cylinder I5 relative to the piston II.

The restricted orifice member I76 acts as a safety device to prevent unintended movement of the plunger I05 Within the pilot valve MI in case leakage should occur past the plunger resistance valve II5. Assuming conditions with pressure in the pipe line I43, if leakage should occur past the plunger of the valve I I before said valve should open, said leakage may pass through re-- stricted orifice member I15 back to the drain line I45, whereby said leakage will not cause the unintended shifting of plunger I05. However, said orifice member I76, being restricted, will not in- -terfere with the application of the necessary pressure to said plunger I05 when resistance valve I I5 has been opened. Likewise, the restricted orifice member I05 prevents the unintended shifting of plunger I05 from its left-hand position to its right-hand position. Assuming that fluid under pressure is being delivered to pipe line I44, if said fluid should leak past the plunger of resistance valve. IIQ, said leakage fluid may pass through restricted orifice member I65 back to the drain line I45. However, said orifice member I65, being restricted, will not prevent the application of fluid pressure to the left-hand extremity of plunger I05 when resistance valve H9 is open.

The fluid pressure system, it will be noted, is entirely closed, so that dirt or foreign matter cannot have access to the fluid within said system. Assuming that the pipe lines, cylinders and other parts of the fluid pressure system are clean .when the fluid is first charged into said system, there is no danger, from a practical -standpoint, of clogging or other disturbances due to dirt or other foreign matter.

.The' present invention has the advantage that flexible or telescoping pipe connections between the source of fluid pressure and the cylinders which utilize said pressure are rendered unnecessary. Furthermore, inasmuch as the tool slide cylinders are all connected up in series with one another, no mechanical connections or other mechanisms are required for transmitting power to the various slides. A further advantage resides in the fact that reversal of the platen and tool slides from forward movement to reverse movement results from the building up of pressure. Consequently, if an abnormal resistance should be encountered in the forward or feeding movement of any of the slides, pressure will build up sufliciently in thepipe line I43 and resistance valve II5 to move the plunger I05 of the pilot valve IM to its left-hand position, which is the position for reversing the control valve 85 to cause the delivery of fluid through the pipe line I44 to cause reverse or retreating movement of the platen and the tool slides.

One embodiment of.the present invention has been described in detail. Many modifications therein will occur to those skilled in the art. It is intended that the particular disclosure shall be considered in an illustrative and not in a limiting sense. Therefore it is intended to cover all such modifications that fall within the scope of the appended claims.

What is claimed is- 1. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, and control means responsive to pressure within said pipe lines for controlling the direction of flow of fluid from said source to said opuerating means, said tool slides, fluid pressure responsive *means, source and pipe lines all being carried by said platen as a unit.

2. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, control means responsive to pressure within said pipe lines for controlling the direction of flow of fluid from said source to said operating means, said tool slides, fluid pressure responsive means, source and pipe lines all being carried by said platen as a unit, fluid pressure responsive means car-- ried by said platen for operating said platen, and pipe lines carried by said platen for communicating fluid pressure from said source to said last mentioned fluid pressure responsive means.

3. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, control means responsive to pressure withinsaid pipe lines for controlling the direction of flow of fluid from said source to said operating means, said tool slides, fluid pressure-responsive' means, source and pipe lines all being carried by said platen as a unit, fluid pressure' responsive means carried by said platen for operating said platen, pipe lines carried by said platen for communicating fluid pressure from said source to said last mentioned fluid pressure responsive means, and means responsive to the movement of said platen along-said bed for controlling the amount of fluid delivered per unit of time by said source.

4. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, and control means responsive to pressure within said pipe lines for controlling the direction of flow of fluid from said source to said operating means, said source, pipe lines and fluid pressure responsive means being connected in a series circuit.

5. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, and control means for said source responsive to pressure within said pipe lines for controlling the direction of flow of fluid from said source to said operating means, said source, pipe lines and fluid pressure responsive means being connected in a series circuit, said fluid pressure responsive means, source and pipe lines all being carried by said platen as a unit.

6. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, control means for said source responsive to pressure within said pipe lines ior'controlling the direction of flow of fluid from said source to said operating means, said source, pipe lines and fluid pressure responsive means being connected in a series circuit, other fluid pressure responsive means carried by said platen for operating said platen, and pipe lines for communicating fluid pressure from said source to said last mentioned fluid pressure responsive means.

1. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, control means for said source responsive to pressure within said pipe lines for controlling the direction of flow oi fluid from said source to said operating means, said source, pipe lines and fluid pressure responsive means being connected in a series circuit, other fluid pressure responsive means carried by said platen for operating said platen, pipe lines for communicating fluid pressure from said source to said last mentioned fluid pressure responsive means, and means responsive to the movement of said platen along said bed for controlling the amount of fluid delivered per unit of time by said source.

8. 171 combination, aplaten, a bed for'carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides,

other fluid pressure responsive means for o zaerat-= ing said tool slides, 51. common. source of fluid pressure, pipe lines connecting said other fluid pressure responsive. means in a series circuit with said source, pipe lines connectingsaid first mentioned fluid pressure responsive means to said, source, and a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value.

9. In combination, a platen, a bed forcarrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source oi fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said first menaooaoia tioned fluid pressure responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, and means responsive to movement of said platen along said bed for controlling the output of said source to control the rate of flow of fluid from said source.

10. In combination, a platen, a bed for carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said first mentioned fluid pressure responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, and control means for said source responsive to the pressure developed thereby for reversing the direction of flow of fluid from said source.

11. In combination, a platen, a bed for carry ing said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said first mentioned fluid pressure responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, means responsive to movement of said platen along said bed for controlling the output of said source to control-the rate of flow of fluid from said source, and control means for said source responsive; the pressure developed thereby for reversing thedire'ction of flow of fluid from said source.

12. In combination, a platen, a bed for carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said fir's't mentionedkfluid'fpressure rf'sponsive means to said source,-and'a resistanc' fvalve in said series circuittor stopping flow offluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, said toolslides, fluid pressure responsive means, source andijpipe lines all being carried by said platen as a unit.

13. In combination, a platen, a bed for carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid ,pressuren pipe lines connecting said other fluid pressure responsiye means in a series circuit with said source, pipe lines connecting said first mentioned fluid pressure" responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, and means responsive to move ment of said platen along said bed for controlling the output of said source to control the rate of flow of fluid from said source, said tool slides, fluid pressure responsive means, source and pipe lines all being carried by said platen as a unit.

14. In combination, a platen, a bed for carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said first mentioned fluid pressure responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, and control means for said source responsive to the pressure developed thereby for reversing the direction of flow of fluid from said source, said tool slides, fluid pressure responsive means, source and pipe lines all being carried by said platen as a unit.

15. In combination, a platen, a bed for carrying said platen, fluid pressure responsive means for moving said platen along said bed, tool slides, other fluid pressure responsive means for operating said tool slides, a common source of fluid pressure, pipe lines connecting said other fluid pressure responsive means in a series circuit with said source, pipe lines connecting said first men tioned fluid pressure responsive means to said source, a resistance valve in said series circuit for stopping flow of fluid from said source to said other fluid pressure responsive means until pressure developed by said source has reached a predetermined value, means responsive to movement of said platen along said bed for controlling the output of said source to control the rate of flow of fluid from said source, control means for said source responsive to the pressure developed thereby for reversing the direction of flow of fluid from said source, said tool slides, fluid pressure responsive means, source and pipe linesall being carried by said platen as a unit.

16. In combination, a supporting member, a

I plurality of tool slides carried thereby, a cylinder cooperatively associated with each of said tool slides, a common source of fluid pressure, pipe lines connecting said source and said cylinders in series relationship with one another, each of said cylinders having a piston movable relative thereto, the exhaust side of each of said cylinders, with the exception of the last thereof,

considered in the direction of forward fluid flow from said source, being of larger capacity than the intake side of the next succeeding cylinder whereby to insure complete forward movement of said tool slides under the influence of said fluid pressure.

1'7, In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder cooperatively associated with each of said tool slides, a common source of fluid pressure, said source being reversible, pipe lines connecting said source and said cylinders in series relationship with one another, each of said cylinders having a piston movable relative thereto, the exhaust side of each of said cylinders, with the exception of the last thereof, considered in the direction of forward fluid flow from said source, being of larger capacity than the intake side of the next succeeding cylinder whereby to insure complete forward movement of said tool slides under the influence of said fluid pressure, and other pipe lines disposed in parallel with one another be tween said source and all but the first of said cylinders in said series circuit considered in the direction of reverse fluid movement within said series circuit to supply sufi'icient fluid to said cylinders to cause corresponding reverse movement of the tool slides throughout their full ranges of travel.

18. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders, considering'one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, and conduit means for conducting pressure from the exhaust side of said other cylinder back to said source.

19. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a

source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, and conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, the capacity of the outlet side of said one cylinder being greater than the capacity of the inlet side of said other cylinder.

20. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of 'said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, control means for controlling the direction of fluid movement from and to said source, and means responsive to the pressure of the fluid delivered by said source for reversing said control means.

21. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluidpres-,

sure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, the cathe fluid delivered by said source for reversing said control means.

22. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of. said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of. said other. cylinder back to said source, control means for controlling the direction of fluid movement from and to said source, means responsive to the pressure of the fluid delivered by said source for reversing said control means, and a pipe line between said source and said exhaust side of said one cylinder for making up the deficit of fluid deliveredback to said one cylinder in the case of reverse fluid flow from said source.

23. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, the capacity of the outlet side of said one cylinder being greater than the capacity of the inlet side of said other cylinder, control means for controlling the direction of fluid movement from and to said source, means responsive to the pressure of the fluid delivered by said source for reversing said control means, and a pipe line between said source and said exhaust side of said one cylinder for making up the deficit of fluid delivered back to said one cylinder in the case of reverse fluid flow from said source.

24. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, the capacity of the outlet side of said one cylinder being greater ,than the capacity of the inlet side of said other cylinder, and pipe lines for delivering excess fluid from the exhaust side of each of said cylinders except the last thereof back to said source.

25. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders, conduit means for conducting pressure from the exhaust side of said other cylinder back to said source, the capacity of the outlet side of said one cylinder being greater than the capacity of the inlet side of said other cylinder, control means for controlling the direction of fluid movement from and to said source, means responsive to the pressure of the fluid delivered by said source for reversing said control means, and pipe lines for delivering excess fluid from the exhaust side of each of said cylinders except the last thereof back to said source.

26. In combination, a supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, a piston within each of said cylinders, said cylinders and pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means between said source and the inlet side of one of said cylinders considering one direction of fluid pressure from said source, conduit means connecting the exhaust side of said one cylinder to the inlet side of another of said cylinders. conduit means for conducting pressure from the exhaust side of said other cylinder back to said source. the capacity of the outlet side of said one cylinder being greater than the capacity of the inlet side of said other cylinder, control means for controlling the direction of fluid movement from and to said source, means responsive to the pressure of the fluid delivered by said source for reversing said control means, a pipe line between said source and said exhaust side of said one cylinder for making up the deficit of fluid delivered back to said one cylinder in the case of reverse fluid flow from said source, and pipe lines for delivering excess fluid from the exhaust side of each of said cylinders except the last thereof back to said source.

27. In combination, a support, a plurality of tool slides carried thereby, a cylinder for each of of said tool slides, each of said cylinders having a piston therein, said cylinders and said pistons being cooperatively associated with said tool slides, a source of fluid pressure. conduit means connecting said source of fluid pressure to one side of one of said cylinders, conduit means connecting the second side of said one cylinder to one side of another of said cylinders, conduit means connecting the second side of said other cylinder back to said source, said second side of said one cylinder having a greater capacity than said one side of said other cylinder whereby fluid delivered from said second side of said one cylinder will more than fill said one side of said other cylinder, and conduit means for conducting said excess fluid back to said source.

28. In combination, a support, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, each of said cylinders having a piston therein, said cylinders and said pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means connecting said source of fluid pressure to one side of one of said cylinders, conduit means connecting the second side of said one cylinder to one side of another of said cylinders, conduit means connecting the second side of said other cylinder back to said source, said second side of said one cylinder having a greater capacity than said one side of said other cylinder whereby fluid delivered from said second side of said one cylinder will more than fill said one side of said other cylinder, conduit means for conducting said excess fluid back to said source. and conduit means connecting said source to said second side of said one cylinder. 29. A supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool Slides, each of said cylinders having a piston therein, said cylinders and said pistons being c ooperatively associated with said tool slides, a source of fluid pressure, conduit means connecting said source'and said cylinders in a series circult, each of said cylinders having a first and seco nd side relative to its corresponding piston, said source being connected through certain of said conduit means to the first side of one of said cylinders, considering fluid movement in one direction in said series circuit, said second side of each of said cylinders, except the last of said-cylinders, being connected to the first side of the next succeeding cylinder in said series circuit.

30. A supporting member, a plurality of tool slides carried thereby, a cylinder for each of said tool slides, each of said cylinders having a piston therein, said cylinders and said pistons being cooperatively associated with said tool slides, a source of fluid pressure, conduit means connecting said source and'said cylinders in a series circuit, each of said cylinders having a first and second side relative to its corresponding piston, said source being connected through certain of said conduit means to the first side of one of said cylinders, considering fluid movement in one direction in said sei'ies circuit, said second side of each of said cylinders, except the last of said cylinders, being connected to the first side of the next succeeding cylinder in said series circuit, said second side of each cylinder being of larger capacity than said first side of its next succeeding cylinder, conduit means'including an obstruction responsive to pressure connecting said second side of each of said cylinders except the last thereof back to said source, and conduit means connect-' ing said source with said second side of each of said cylinders except the last thereof, said last mentioned conduit means including obstructions yieldable to pressure from said source in one direction and non-yieldable to pressure in the opposite direction.

31. In a machine tool, in combination, a platen, fluid pressure responsive means for operating said platen, a plurality of tool slides carried by said platen, fluid pressure responsive means for operating each of said tool slides, a source of pressure carried by said platen, conduit means connecting said fluid pressure responsive means for said tool slides in a series circuit, control means for controlling the direction of fluid pressure delivered by said source, pilot means for reversing said control means, and a resistance valve connecting said source to said pilot means, said resistance valve having a greater resistance than is required to operate said platen and said slides under normal operation.

32. In a machine tool, in combination, a platen, fluid pressure responsive means for operating said platen, a plurality of tool slides carried by said platen, fluid pressure responsive means for operating each of said tool slides,-a source of pressure carried by said platen, conduit means connecting said fluid pressure responsive means for said tool slides in a series circuit, control means for controlling the direction of fluid pressure delivered by said source, pilot means for reversing said control means, a resistance valve connecting said source to said pilot means, said resistance valve having a greater resistance than is required to operate said platen and said slides under normal operation, and a restricted orifice member for shunting back to said source fluid which has leaked past said resistance valve.

33. In a machine tool, in combination, a platen, fluid pressure responsive means for operating said platen, a plurality of tool slides carried by said platen, fluid pressure responsive means for operating each of said tool slides, a source oi. pressure carried by said platen, conduit means connecting said source and said fluid pressure responsive means for said tool slides in a series circuit, control means for controlling the direction of fluid pressure delivered by said source, pilot means for reversing said control means, a resistance valve adapted to connect said source to said pilot means when said source is delivering pressure in a direction to cause forward movement of said platen, a resistance valve adapted to connect said source to said pilot means when said source is delivering pressure in the opposite direction, said first mentioned resistance valve having a resistance greater than that required to move said platen and said tool slides to the limits of their forward movement under normal operating conditions, the other of said resistance valves having a resistance less than that required to move said platen to the limits of its retreating movement under normal operating conditions.

34. In a machine tool, in combination, a platen, fluid pressure responsive means for operating said platen, a. plurality of tool slides carried by said platen, fluid pressure responsive means for operating each of said tool slides, a source of pressure carried by said platen, conduit means connecting said source and said fluid pressure responsive means for said tool slides in a series circuit, control means for controlling the direction of fluid pressure delivered by said source, pilot means for reversing said control means, a resistance valve adapted to connect said source to said pilot means when said source is delivering pressure in a direction to cause forward movement of said platen, a resistance valve adapted to connect said source to said pilot means when said source is delivering pressure in the opposite direction, said first mentioned resistance valve having a resistance greater than that required to move said platen and said tool slides to the limits of their forward movement under normal operating condition, the other of said resistance valves having a resistance less than that required to move said platen to the limits of its retreating movement under normal operating conditions, each of said resistance valves being provided with a restricted orifice member for conducting fluid back to said source which leaks past its said corresponding resistance valve.

35. In a lathe, in combination, a bed, a platen movable thereon, fluid pressure responsive means carried by said platen for moving said platen, tool slides carried by said platen and movable relative to said platen, fluid pressure responsive means for operating said tool slides, and. a common source of fluid pressure carried by said platen for delivering fluid pressure to all of said fluid pressure responsive means.

36. In a lathe, in combination, a bed, a platen movable thereon, tool slides carried by said platen and movable relative to said platen, fluid pressure responsive means for operating said tool slides, and a common source of fluid pressure carrled by said platen for delivering fluid pressure to said fluid pressure responsive means.

37. In a lathe, in combination, a bed, a platen till movable thereon, tool slides carried by said platen and movable relative to said platen, fluid pressure responsivev means for operating said tool slides, a common source of fluid pressure carried by said platen for delivering fluid pressure to said fluid pressure responsive means, and means responsive to resistance to movement of said slides for controlling said source to cause reversal of movement of said tool slides and said platen.

38. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides carried by said platen, fluid pressure responsive means for operating said slides, a common source of fluid pressure, and pipe lines connecting said fluid pressure responsive means and said source in a series circuit.

39. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides pressure responsive means being connected in a series circuit.

40. In a machine tool, in combination, a bed, a platen movable thereon, a plurality of tool slides, fluid pressure responsive means for operating said slides, a common source of fluid pressure, pipe lines connecting said source with said fluid pressure responsive means, and control means responsive to pressure within said pipe lines for controlling the direction of flow of fluid from said source to said operating means.

WILLIAM H. FOSTER. 

